The metabolism of LDL cholesterol and its response to dietary intervention in men has been widely studied, but few evaluations of LDL metabolism in women have been done. It has yet to be demonstrated that LDL cholesterol levels in women respond similarly to various interventions as LDL cholesterol levels in men. The lack of a thorough analysis of serum lipids in women is not surprising. Women have lower initial rates for coronary disease, and their rates for disease do not approach those of men until after age 50. From epidemiological data, LDL cholesterol is equally predictive of risk for both men and women over age 50. Studies with small numbers of men and women suggest that women have less of an LDL lowering to a low saturated fat diet then men, and may have a greater HDL lowering on a low fat diet then men. The aim of the current investigation is to 1) determine how effective diet is in lowering LDL cholesterol levels ("diet responsiveness") in postmenopausal hypercholesterolemic women, and compare this responsiveness to that of similar aged men 2) determine the effect of commonly prescribed estrogen/progesterone supplements on diet responsiveness, and 3) determine the effectiveness of the lipid-lowering drug, cholestyramine, in this population.